Environment detection or motion detection is the process of detecting a change in the position of an object relative to its surroundings or a change in the surroundings relative to an object. Motion detection can be achieved by either mechanical or electronic methods. Generally, an infrared sensor, an optical photographing system, a sound or vibration sensor, or a magnetic sensor is employed as the motion detection sensor to perform the motion detection. The infrared sensor is the most commonly used sensor for such detection owing to the better detecting effect and accuracy thereof. However, the detectable angles of the motion-detection sensors are usually limited by installation angles and installation positions of the motion-detection sensors, and the motion-detection sensors can only recognize the changes of the detected images within a specific zone. When the detectable angle of the motion-detection sensor is limited, the motion-detection sensors fail to detect the moving objects efficiently and fail to avoid the interference of surrounding lighting at the same time.
If the presences of the static object or people can't be detected by the motion-detection sensors, the security controls of human and surrounding can't be accomplished. Therefore, the detectable angle of a detecting apparatus has a large influence over the property of the detecting apparatus. By the limitation of the detectable angle, the detecting apparatus must be installed in an optimal position for obtaining the largest detectable angle. It is not easy to adjust the detectable angle of the installed detecting apparatus, and it will consume a lot of manpower to detach or maintain the installed detecting apparatus.
On the other hand, the sensitivity of the detecting apparatus may be affected by the surrounding obviously. When the detected surrounding is changed, the sensitivities of different detecting apparatuses are influenced differently. Consequently, the conventional detecting apparatus fails to provide the detecting module in different type according to the surrounding change and the optimal efficiency of environment monitoring can't be achieved.
Therefore, there is a need of providing a detecting apparatus having a detachable detecting module in order to achieve the purpose of environment monitoring according to the surrounding change and the implements in different environments, and overcome the above drawbacks encountered by the prior arts.